Apparatus for scoring sheet material

ABSTRACT

A cutter assembly for scoring a score line in a surface of sheet material, is connected to the piston of a double-acting pneumatic cylinder and piston operable to urge the cutter assembly towards the surface to be scored.

Umted States Patent 1 1 1 1 3,742,793 Gray et al. July 3, 1973 [54]APPARATUS FOR SCORING SHEET 3,276,302 10/1966 lnsolio 83/8 MATERIAL3,631,766 H1972 Kraakman..... 92/162 3,136,191 6/1964 Madge 83/l2 [751In entors: John McCutcheon Gray. re c t: 3.216.635 11/1965 Lefevre.....83/12 x Jerzy Plonke, Liverpool. both of 2.623.501 12/1952 Audemar92/162 England; Edwin Johnson, Ajax, 2.907.304 10/1959 Macks... 92/162 XOntario, Canada 3,280,677 l/l966 Grzymislawski.. 83/12 X 3.537.345 111970 Luppino 83/12 [73] A lgn e ilkingt n B r mi e 3,399,586 9/1968lnsolio e! 111.. 83/12 Liverpool, England 3,663.071 /1972 Kates 92/162UX [22] Filed: July 2, 1971 [21] App]. No.: 159,124 PrimaryExaminerFrank T. Yosl 1 Attorney-Richard C. Sughrue, Robert J. Slas, Jr.Foreign Application Priority Data and Robert V July 10, 1970 GreatBritain 33,645/

52 11.5.01 83/8, 83/11, 83/12, [57] ABSTRACT v 83/169, 83/639, 92/162[51] Int. 'Cl B26d 3/08 A cutter m y f r ring a c re line in a surface[58] Field of Search 83/12, 11, 8, 639, of sheet e a is connected t thepi t n f a d u- 83/ 169; 92/ 162, ble-acting pneumatic cylinder andpiston operable to urge the cutter assembly towards the surface to be[56] References Cited scored.

UNITED STATES PATENTS 3,198,044 8/ 1965 Clin 83/12 X 10 Claims, 4Drawing Figures PATENTEDJUL3 197s summra APPARATUS FOR SCORING SHEETMATERIAL BACKGROUND OF THE INVENTION The invention relates to apparatusfor scoring sheet material, e.g. glass sheets or continuous glassribbons, prior to breaking the sheet along the score line or lines.

SUMMARY According to the invention apparatus for scoring a score line ina surface of sheet material, comprises a cutter assembly,-and adouble-acting pneumatic cylinder and piston, the cutter assembly beingconnected to the piston whereby the piston is operable to urge thecutter assembly towards the surface to be scored.

Preferably the cutter assembly is mounted on a foot connected to thepiston, said foot having wheels disposed on either side of the cuttingtool of the cutter assembly for engagement with the edges of saidsurface immediately preceding and subsequent to the scoring operation.

Preferably the relative dimensions of the piston and the cylinder arearranged so that there will be a flow of air between said cylinder andpiston during movement of said piston, said air flow being sufficient tocreate an air bearing between said cylinder and piston.

It is also preferred that said cutter assembly is connected to one endof a shaft comprising an extension of the piston, and the cylindercomprises a housing having a passageway through which said shaftprojects, the relative dimensions of the shaft and the passageway beingarranged so that there will be a flow of air between said shaft andpassageway during movement of the piston, said air flow being sufficientto create an air bearing between said shaft and passageway.Flow-assisting shoulders may be provided at the end of the passagewayadjacent the cylinder.

In a case in which the apparatus is adapted to score at least two scorelines in a surface of sheet material, the apparatus includes acorresponding number of cutter assemblies and respective independentlyoperable double-acting pneumatic cylinders and pistons mounted on asupport bar whereby the spacing between the cutter assemblies isvariable.

In one form of the invention the apparatus is adapted to be mountedabove a conveyor, the cutter assembly a or assemblies being adapted tolongitudinally score the upper face of sheet material passed along saidconveyor. The conveyor may be a roller conveyor, the cut-- ter assemblyor assemblies being mounted above a transverse roller of the conveyor.

In another form of the invention there are provided means for moving thecutter assembly or assemblies at an angle across moving sheet material,in a forwardly direction, the angle and speed of the cutter assembly orassemblies being related to the speed of the sheet material whereby theupper face of the sheet material is scored transversely.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation, partly insection and part cut-away, of apparatus by way of example forlongitudinally scoring sheet material,

FIG. 2 is a front elevation of another apparatus for longitudinallyscoring sheet material,

FIG. 3 is a front elevation of apparatus for transversely scoring sheetmaterial, and

FIG. 4 is a side elevation of the apparatus of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, thescoring apparatus comprises a foot 1 adjustably attached to the lowerend of a vertical shaft 2 which is slidably mounted within a housing 3.The housing 3 has machined therein, concentric with the axis of theshaft 2, a cylinder 4. A piston 5 is fastened to the upper end of theshaft 2 and arranged to slide within the cylinder 4. Air lines 6 and 7connect with the cylinder 4 through the housing 3, above and below thepiston 5 respectively. Air may be admitted to the cylinder 4 through oneof the lines 6 or 7 at any desired time. If air is admitted to thecylinder 4 through the line 6, the piston 5 tends to be forced towardsthe bottom of the cylinder, and the shaft 2 and the foot I tend to beforced downwards towards a sheet S travelling beneath the foot. If,however, air is admitted through the line 7, the piston 5 is forced upthe cylinder 4, and the shaft 2 and the foot 1 travel to a retractedposition.

The housing 3 is mounted upon a support 8 which is detachably mountedupon a mounting bracket 9 and held in position thereon by a locking nut10. Projecting from the bottom of the support 8 is an alignment shaft 11which slidably locates in a vertical hole 12 in the foot 1. A cutterassembly 13, comprising a cutting or scoring wheel 14, a carrier 15 anda post 16, is slidably mounted in a downwardly open recess 17 in theunderside of the foot 1, and is retained in the recess by, for example,a retaining ring 18. The cutter assembly may be internally biased inknown manner to an outward or lower position relative to the foot 1,whereby a small amount of relative vertical movement is permittedbetween the cutter assembly 13 and the foot 1.

Aligned with the cutting wheel 14, are free running wheels 19, 20. Thesewheels 19, 20 protect the edges of sheets from damage as the sheet edgestravel beneath the cutter, but whilst the cutter is operating upon thesurface of the sheet S clear of the edges, only the cutting wheel 14 isin contact with the sheet. Typically, there is a clearance of about0.030 inches between the wheels 19, 20 and the sheet surface S.

An air line 21 is connected to a mist lubricator 22 which is mounted bymeans of a bracket 23 fixed to the housing 3: Oil-laden air is carriedfrom the lubricator 22 to the foot 1 by means of a pipe 24, whichconnects with the foot 1 through a union 25. The pipe 24 is light andvery flexible so as not to impede the movement of the foot 1. Apassageway 26 connects with the union 25 and is arranged so that the oilin the air, which enters the foot 1 via the pipe 24 and the union 25,lubricates any movement of the post 16 within the recess 17 and therotation of the cutting wheel 14, and also provides a film of oil on thesurface of the sheet S to facilitate scoring of the surface by thecutting wheel 14.

The shaft 2 passes through the housing 3 into the cylinder 4 through apassageway 28. This passageway 28 is made slightly over-size for theshaft 2 and the piston 5 is made slightly under-size for the cylinder 4.Typically, there is a clearance of about 0.002 ins. between the shaft 2and the passageway 28 and about 0.002 ins. between the piston 5 and thecylinder 4. Thus, when air pressure is applied to the cylinder 4 via theline 6' or the line 7 some air leaks around the piston 5 and also downthe passageway 28 around the shaft 2. This effectively provides airbearings for the shaft 2 and the piston 5 permitting a very quick andresponsive action of the cutting wheel 14 to any variations in the uppersurface of the glass sheet S. To facilitate this small flow of air,flow-assisting shoulders 29, are provided at the upper end of thepassageway 28, i.e. at the end of the passageway adjacent the cylinder.

In operation, the apparatus is positioned above a transverse roller 27of a horizontal roller conveyor. A sheet S, e.g. of glass, travels onthe conveyor towards the foot 1 in the direction shown by arrow A inFIG. 1. The foot is in the downward position with air pressure appliedto the cylinder 4 via the line 6. When the leading edge of the sheet Sreaches the foot 1 it strikes a cam-like leading surface 30 thereof, andlifts the foot 1. The sheet S then contacts the wheel 19 which lifts thefoot 1 clear of the sheet S ready for the cutting wheel 14 to make alongitudinal score thereon. The wheel 14 is held in contact with thesheet S by a suitable air pressure in the cylinder 4 acting upon thepiston 5 whilst the sheet S is carried over the roller 27. When thewhole sheet S has passed under the cutting wheel 14 the foot 1 is heldclear of the trailing edge of the sheet S by the wheel 20 so that theedge is not damaged by contact with the foot 1. When the sheet S is nolonger in contact with the wheel 20 the foot 1 is returned to itsdownward position ready for the delivery of the next sheet S.

As previously explained, the foot 1, shaft 2 and piston 5 areconstructed so as to have a very low inertia and the piston 5 and shaft2 move very freely due to their air lubrication. This enables the foot 1to react very rapidly to any irregularities in the surface being cut orany undulations in the sheet S. In this way a continuous score line isobtained on the surface of the sheet S, instead of the discontinuousline often produced with conventional equipment which does not have thenecessary rapid response to be able to follow exactly the surface beingscored.

It will be appreciated that where a plurality of longitudinal scorelines are required on the sheet S a corresponding plurality of cutterassemblies 13 as described above may be employed. Conveniently, thecutter assemblies are operable independently and adjustably mounted on asupport beam so that the spacing between adjacent cutters can beadjusted to provide the required spacing between adjacent score lines.FIG. 2 shows, by way of example, an apparatus having two cutterassemblies 31, 32 individually operable by means as described above withreference to FIG. 1. These cutter assemblies 31, 32 and their respectiveoperating means 35, 36 are adjustably mounted side-byside on a supportbeam 33 having a graduated scale 34 to 'facilitate the scoring of twoparallel longitudinal score lines of the sheet S, a predetermineddistance apart.

As will be appreciated, the apparatus of FIG. 1 and that of FIG. 2 areeach designed for scoring one or more score lines on a sheet in thedirection in which the sheet is travelling. The sheet is then brokenalong the score line or lines.

Referring to FIGS. 3 and 4, an apparatus is illustrated for scoring asheet transversely, i.e. perpendicularly to the direction in which thesheet is travelling. As before, a cutting assembly 13 is mounted on afoot 1 depending from a vertically movable shaft 2. Air to the cylinder(not shown) internally of the housing 3 is again fed through one of thepipes 6, 7, the selection being controlled by a solenoid valve 40interconnecting the pipes 6, 7 and a common pipe 41. The feed pipe 6includes an air pressure gauge 42 since it is this pipe 6 through whichair is fed during the scoring operation. In this embodiment thealignment shaft II is reversed and, at its upper end, is provided with apair of nuts 43 to act as an adjustable limit stop for the lowermostposition of the foot 1.

The housing 3 is mounted on a back plate 44 provided with four pulleys46 on its reverse side for running along horizontal guide rails (notshown) secured to a fixed structure, the upper pulleys running on top ofthe upper guide rail and the lower pulleys running beneath the lowerguide rail. The plate 44 is driven back and forth along the guide railsby an endless metal belt (not shown) of which the upper run is split andthe ends of the belt are fixed to the plate 44 at the parts 45, the beltbeing driven by reversible drive means. At each side of the plate 44,there are provided a pair of buffers 47 which abut against appropriatestops at each end of the run of the plate.

In the operation of this embodiment the apparatus is driven in thedirection of arrow B in FIG. 3, across and at an angle to the advancingsheet, the apparatus having a forward speed component and a lateralspeed component whereby the apparatus moves forwardly and laterallywith'respect to the sheet at a selected angle and speed relative to theforward movement of the sheet so that a score line perpendicular to thedirection of travel of the sheet is made on the top surface of thesheet.

If desired, the apparatus of this embodiment may be provided with a mistlubricator 22 in the same manner as the first embodiment illustrated inFIG. 1.

One advantage of all the embodiments described above is that theapparatus may be employed to score different thicknesses of sheetmaterial without the need for complex adjustment of the apparatus.

The invention is not limited to the specific details of the embodimentsdescribed above. For example, each scoring apparatus may be employed forscoring one or more score lines on other sheet material besides glasssheets, for example glass ribbons or sheets of other materials, e.g.acrylic sheets.

Further, the apparatus described above as being used for scoringindividual sheets may be used for scoring a continuous ribbon of sheetmaterial either longitudinally or transversely, i.e. perpendicularly tothe direction of travel of the ribbon. Yet further, the apparatus can beused in producing discontinuous or interrupted score lines, i.e. scorelines which commence and/or terminate at a position on the surface ofthe sheet material and do not extend from one edge thereof to another.In this case the cutting head can be lowered onto the surface of thesheet material to commence a score line at a required position byintroduction of pressure air through the line 6 into the cylinder 4, andcan be raised from the sheet material to terminate a score line at arequired position by introduction of pressure air through the line 7into the cylinder 4. It has been found that with the describedarrangement a rapid lowering and raising of the cutting head can beachieved.

Also, the sheet material being scored may be travelling horizontally asdescribed above, but alternatively may be travelling vertically or at anangle inclined to the horizontal.

Furthermore, the sheet material being scored may be supported on othertypes of conveyor besides a roller conveyor, e.g. a belt conveyor.

We claim:

1. Apparatus for scoring a score line in a surface of glass sheetmaterial, comprising a cutter assembly and a double acting pneumaticcylinder and piston, the cutter assembly being connected to the pistonwherebythe piston is operable to urge the cutter assembly towards thesurface to be scored, said cylinder and piston comprising a housingdefining the cylinder in which the piston is slidable, said housinghaving an apertured end wall, and a shaft connected with the piston andextending axially of the cylinder through said passageway in the wall ofthe housing so as to project therefrom, the cutter assembly beingconnected to the projecting end of the shaft, and the piston beingunder-size relative to the cylinder and the shaft under-size relative tothe passageway thereby permitting flow of air between the piston and thecylinder wall and between the shaft and the passageway wall, whereby twospaced air bearings are provided facilitating controlled movement of thecutter assembly.

'2. Apparatus according to claim 1, wherein the cutter assembly ismounted on a foot connected to the piston, said foot having wheelsdisposed on either side of the cutting tool of the cutter assembly forengagement with the edges of said surface immediately preceding andsubsequent to the scoring operation.

3. Apparatus according to claim 2, wherein the foot has a lead-insurface disposed on the other side of one of the wheels from the cuttingtool, the leading edge of a surface to be scored engaging said lead-insurface before engaging said one wheel.

4. Apparatus according to claim 1, wherein flow-- -assisting shouldersare provided at the end of the passageway adjacent the cylinder.

5. Apparatus according to claim 1, including means to maintain thealignment of the cutter assembly.

6. Apparatus according to claim 1, including a mist lubricator wherebyoil-laden air may be supplied to the cutter assembly.

7. Apparatus according to claim 1, for scoring at least two score linesin a surface of sheet material, including a corresponding number ofcutter assemblies and respective independently operable double-actingpneumatic cylinders and pistons mounted on a support bar whereby thespacing between the cutter assemblies is variable.

8. Apparatus according to claim 1, adapted to be mounted above aconveyor, the cutter assembly being adapted to longitudinally score theupper face, of a sheet material passed along said conveyor.

9. Apparatus according to claim 8, wherein the conveyor is a rollerconveyor, the cutter assembly being mounted above a transverse roller oftheconveyor.

10. Apparatus according to claim 1, including means for moving thecutter assembly at an angle across moving sheet material, in a forwardlydirection, the angle and speed of the cutter assembly being related tothe speed of the sheet material whereby the upper face of the sheetmaterial is scored transversely.

1. Apparatus for scoring a score line in a surface of glass sheetmaterial, comprising a cutter assembly and a double acting pneumaticcylinder and piston, the cutter assembly being connected to the pistonwhereby the piston is operable to urge the cutter assembly towards thesurface to be scored, said cylinder and piston comprising a housingdefining the cylinder in which the piston is slidable, said housinghaving an apertured end wall, and a shaft connected with the piston andextending axially of the cylinder through said passageway in the wall ofthe housing so as to project therefrom, the cutter assembly beingconnected to the projecting end of the shaft, and the piston beingunder-size relative to the cylinder and the shaft undersize relative tothe passageway thereby permitting flow of air between the piston and thecylinder wall and between the shaft and the passageway wall, whereby twospaced air bearings are provided facilitating controlled movement of thecutter assembly.
 2. Apparatus according to claim 1, wherein the cutterassembly is mounted on a foot connected to the piston, said Foot havingwheels disposed on either side of the cutting tool of the cutterassembly for engagement with the edges of said surface immediatelypreceding and subsequent to the scoring operation.
 3. Apparatusaccording to claim 2, wherein the foot has a lead-in surface disposed onthe other side of one of the wheels from the cutting tool, the leadingedge of a surface to be scored engaging said lead-in surface beforeengaging said one wheel.
 4. Apparatus according to claim 1, whereinflow-assisting shoulders are provided at the end of the passagewayadjacent the cylinder.
 5. Apparatus according to claim 1, includingmeans to maintain the alignment of the cutter assembly.
 6. Apparatusaccording to claim 1, including a mist lubricator whereby oil-laden airmay be supplied to the cutter assembly.
 7. Apparatus according to claim1, for scoring at least two score lines in a surface of sheet material,including a corresponding number of cutter assemblies and respectiveindependently operable double-acting pneumatic cylinders and pistonsmounted on a support bar whereby the spacing between the cutterassemblies is variable.
 8. Apparatus according to claim 1, adapted to bemounted above a conveyor, the cutter assembly being adapted tolongitudinally score the upper face of a sheet material passed alongsaid conveyor.
 9. Apparatus according to claim 8, wherein the conveyoris a roller conveyor, the cutter assembly being mounted above atransverse roller of the conveyor.
 10. Apparatus according to claim 1,including means for moving the cutter assembly at an angle across movingsheet material, in a forwardly direction, the angle and speed of thecutter assembly being related to the speed of the sheet material wherebythe upper face of the sheet material is scored transversely.